1. Technical Field
This invention relates to a method for the production of articles of manufacture comprising a web product soaked or moistened with a product having a liquid base. The invention also relates to a winding machine for the production of rolls of soaked or moistened web material.
2. State of the Art
Products known as refreshing, disinfectant or detergent wipes comprising sheets of paper material soaked in an aqueous solution of detergents, soaps and perfumed or other substances are currently manufactured. Normally these wipes are packed individually in sealed sachets. In some cases multiple packs are constructed, which contain a plurality of moistened wipes which can be removed from the pack individually.
The object of the present invention is to provide a method and a device for the production of rolls of web material, for example but not exclusively of absorbent paper material, soaked or moistened with substances having a liquid base containing detergents, soaps, perfumed oils, disinfectants or other components.
Substantially the invention provides a method for the production of rolls of wound web material in which the web material is fed along a feeding path to a winding zone where it is wound to form rolls, and in which characteristically a moistening product is applied to the web material upstream from the winding zone. The roll is obtained in this way by winding a web material which has already been impregnated with detergent, deodorant, moisturizing, disinfectant or other products with which it is desired that the finished product be impregnated.
In practice the method comprises the stages of:
feeding the web material along a feed path to a winding zone in which said web material is wound to form a first roll,
when winding of said first roll is complete, acting on said web material in an interruption zone to produce an interruption in the web material and produce a free end of web material,
beginning the winding of a second roll from said free end.
In accordance with the invention the method is characterized in that a moistening product is applied to the web material along said feed path between the interruption zone and the winding zone.
By interruption zone is generally meant a zone along the web material feed path in which a force is applied to the latter which is intended to cause the breakage, tearing, cutting or in general interruption of the web to conclude the winding of a first roll and produce the free leading edge for formation of a subsequent roll. The interruption zone may be that in which a blade acts on the web material in order to cut it. Alternatively, the interruption zone may be the zone in which a moving member pinches the web material against a fixed member or another member moving at an appropriately different speed. For example the interruption zone may be a zone in which an oscillating or rotating member presses the web material against a feed and/or winding member, for example a winding roller or belt. Alternatively, it may be a zone in which a tubular winding core or a winding mandrel presses the web material against the feed or winding member, or against a fixed or moving surface. In general, the interruption zone may coincide with the zone in which the free end of web material is formed; this occurs for example when a cutting blade is used. However, more generally, the interruption zone need not necessarily coincide with the zone where the free end is produced, which latter may typically be downstream from the interruption zone, at a point where tearing occurs as a result of overtensioning of the web material.
The method may advantageously be based on a winding system known as a peripheral or surface winding system, that is one in which the roll is formed in a winding cradle formed by winding members, such as typically rollers or belts or combinations thereof which contact the surface of the forming roll and keep it rotating.
In this embodiment it may be provided that the web material is passed round one of the winding members. In this case the moistening product is applied, for example by spraying, to the web material while the latter travels around the winding member. In this way the advantage is achieved that the web material is supported by the surface of the winding member while application takes place, and therefore prevents damage to the material. Also, the moistening product is applied in this way immediately upstream from the point where the web material is wound onto the forming roll, and furthermore the web material is substantially supported by the winding member from the point at which the moistening product is applied to the point where it is wound. This has the result that the weakening of the web material resulting from absorption of the moistening product does not result in any risk of breakage during winding. This aspect is particularly important in that the web material typically comprises paper known as xe2x80x9ctissuexe2x80x9d, non-woven fabric or other material of little substance and mechanical strength which tends to weaken as a result of the absorption of liquids.
It may also be provided that the web material is passed around a cutting roller and passes from this to one of the peripheral winding members. In this case the liquid may be applied to the web material while it is passed around the cutting roller, advantageously downstream from the cutting zone. In this case too there is substantial support for the moistened web material until it is wound.
More generally it is particularly advantageous to provide that the liquid product be applied downstream of the changeover zone. By changeover zone is meant generically that zone in which the formation of a new roll takes place at the start of each winding. The changeover zone may be a zone in which the leading end of the web material is transferred to a winding mandrel or core. If winding takes place without a core or without a mandrel the changeover is the stage in which the leading edge of the web material begins to wind or curl upon itself to form the initial core and thus the first turns of a new roll.
Means for interrupting the web material are normally provided along the path traveled by the web material. The interruption of web material makes it possible to interrupt winding of the latter onto a now complete roll and begin the winding of a new roll.
When means for interruption of the web material are provided the moistening product is applied between the position at which the means of interruption act and the point at which winding of the roll takes place. The means of interruption may be any known means, for example a blade, a presser which breaks the web material by pinching it against a suitable surface, for example even the surface of one of the winding members, a vacuum system, or other means suitable for achieving interruption of the web material through cutting, tearing, perforation and tearing, overtensioning or otherwise.
In accordance with a particularly advantageous embodiment of the method according to the invention, a rolling plate is provided upstream from the winding zone along the feed path for the web material. The roll of web material is caused to roll along the rolling plate in the first stage of winding, towards the winding cradle where the roll is formed, winding being completed between the winding members. Means for spraying the moistening product are also provided at a terminal part of the winding plate close to the winding cradle.
The roll is preferably wound without a central winding core, for example using a winding system of the type described in U.S. Pat. No. 5,639,046 or U.S. Pat. No. 5,538,199.
In accordance with the invention a winding machine is provided for the production of rolls of wound web material which comprises a feed path for the web material and winding means to wind the web material and form said rolls. Characteristically, applicator members for applying a moistening product to the web material while this is fed along said feed path are provided upstream from the winding means.
The winding means are advantageously of the surface or peripheral type, that is they comprise peripheral winding means which form a winding cradle and which are in contact with the outer surface of the forming roll and which cause it to rotate by transmitting rotational movement by friction. In this case the winding means comprise belts, winding rollers or combinations thereof, or equivalent peripheral winding members. The applicator members are advantageously and preferably associated with one of the peripheral winding members along which the web material is passed prior to reaching the winding point.
Peripheral winding may take place on a central winding core which is then retained within the finished product. In this case the winding core is preferably constructed of a plastics or otherwise non-absorbent material, in order to retain a uniform liquid content throughout the wound web material, including the first turns. Attentively the winding core may comprise a removable mandrel which is subsequently removed from the wound roll. In accordance with the preferred embodiment however, winding takes place without a central core and without a mandrel, the leading end of the web material being wound onto itself.
In accordance with a particularly advantageous embodiment of the winding machine according to the invention, a rolling plate is located along the web material feed path upstream from the winding zone. The rolling plate ends close to the winding cradle and extends partly around a peripheral winding member around which the web material is fed, forming in effect a transfer channel for said web material with said winding member. In this configuration the applicator members are advantageously associated with the terminal end of the plate which lies closest to the winding cradle.
The applicator members may be constructed within said rolling plate, for example in a terminal portion thereof of comb construction. In this case provision may be made for the applicator members to be constructed in the form of nozzles formed by holes made in the plate. The plate itself may be a member formed from a plurality of assembled components, for example a sheet and a terminal comb portion which together form a single piece.
Further possible advantageous features and embodiments of the winding machine and the method according to the invention are indicated in the appended claims.